Camera modules for vehicles have in general an objective having a lens mount and at least one lens, an image sensor, and a bearer device on which the image sensor is mounted and contacted. For this purpose, the bearer device is fashioned for example as a circuit board. The objective is accommodated in an objective receptacle (lens holder) so as to be capable of longitudinal displacement in order to enable adjustment. The objective receptacle is generally fastened on the bearer device.
The adjustment takes place by acquiring for example a test pattern in a relevant object width, and evaluating the image signals of the image sensor in order to determine a longitudinal position of the objective with the best possible contrast and to adjust it so that the image sensor is in the image plane. Subsequently, the objective is fixed on the objective receptacle. The constructive unit made up of the bearer device with image sensor and objective fixed on the bearer device, designated overall as the imager module, is then installed in a camera housing for protection against external influences and for installation in the vehicle.
The electrical connection of the image sensor should take place as far as possible without force, in order to keep the influence on the positional stability in the image plane low. The assembly made up of the image sensor and the objective defines the optical axis and may be capable of being mounted in the camera housing in such a way that the central axis of view, i.e. the axis of symmetry of the region of acquisition, or opening angle, can be precisely defined.
German patent document DE 10 2009 027 514 A1 discusses such a camera module, in which the objective is fixed on the objective receptacle (lens holder) by an adhesive that cures under UV radiation.
In general, the expensive production from a large number of components having corresponding tolerances, and the problem of determining the axis of view relative to the camera housing, are disadvantageous.